Defendant Christian Gerhartsreiter (C) from Germany arrives for the start of his murder trial at the Los Angeles Superior Court in Los Angeles. (Reuters)

LOS ANGELES (Reuters) - A German man who once posed as a member of the wealthy Rockefeller clan before his secret life in New Hampshire unraveled was accused in a California courtroom on Monday of murdering his landlord in 1985 and then going to great lengths to cover up the death.

The accusations against Christian Gerhartsreiter, whose life of assuming false identities was portrayed in the 2010 made-for-TV movie "Who Is Clark Rockefeller?" came during opening arguments in his murder trial.

Gerhartsreiter, once part of Boston's high society, rose to national prominence after he was arrested in 2008 for abducting his daughter and was revealed to have assumed a fake identity to pose as a member of the Rockefeller family.

While Gerhartsreiter was serving a four-year prison term in Massachusetts for that crime, prosecutors in Los Angeles said they had charged him with the murder of his landlord, John Sohus, who went missing in 1985 along with his wife, Linda.

"You will hear evidence, ladies and gentlemen, that this couple is dead," deputy district attorney Habib Balian told jurors in a downtown Los Angeles court.

At the same hearing, Gerhartsreiter's attorney argued the landlord's long-missing wife was the one who killed him. Linda Sohus is presumed dead, but her body has never been found. Gerhartsreiter is not charged in her death.

The remains of John Sohus, 27, were discovered in 1994 in the backyard of the home in the Los Angeles suburb of San Marino where the couple lived and where Gerhartsreiter had rented a guest house. At the time, Gerhartsreiter used the name Christopher Chichester, prosecutors say.

BLOOD UNDER CARPET

On Monday, prosecutors said their case against Gerhartsreiter would include evidence from investigators who found large amounts of blood beneath the carpets in the guest house he had occupied.

Balian said Gerhartsreiter, who came to the United States as a student from his native Germany in the 1970s, tried to cover up the killing by making it seem the couple was still alive.

After they went missing, cryptic postcards in Linda's handwriting and postmarked from Paris arrived at the homes of Linda's boss, her mother and her best friend, Balian said.

But Linda never boarded an intercontinental plane, had a passport or showed any desire to go to Europe, he said. Balian suggested Gerhartsreiter had someone else mail the postcards from Europe, possibly after forcing Linda to write them.

Linda Sohus also played a prominent role in the narrative Gerhartsreiter's attorney Brad Bailey presented to jurors.

Bailey sought to pin the blame for John Sohus' death on her, arguing that she weighed 200 pounds (91 kilograms) and was physically capable of murdering her husband.

"There will be enough evidence for you to reasonably conclude it could well have been John Sohus' vanished wife Linda" who committed the killing, Bailey told jurors.

Bailey said he would not try to deny that Gerhartsreiter had assumed a number of identities over the years.

"As all of you know, when you have an old and a cold case, it's sometimes human nature to blame the drifter or the grifter or the con artist, isn't it?" Bailey told jurors.

Gerhartsreiter faces a maximum sentence of life in prison if convicted of the murder of John Sohus.